1890.] NATURAL SCIENCES OF PHILADELPHIA. 165 



Horizon and localities. Kinderhook beds : Burlington, Iowa ; and 

 Lodi, Ohio. 



This is one of the smallest of the Lower Carbonic species of the 

 genus ; but may have attained a larger size than the type specimen 

 indicates. A large form from Lodi, Ohio, labeled Platyceras 

 cornuforme by Meek seems to be more closely related to C. paralius 

 (W. & W.) than with species in question. 



Capulus haliotoides (Meek & Worthen). 



Platyceras haliotoides Meek cS; Worthen, 1S6G. Proc. Acad. Nat. Sci., Phila., 

 July, 1866, p. 264. 



Platyceras haliotoides'Wtt^ ik.\^<:>\\\\&r\, 1868. Gaol. Sur. Illinois, vol. Ill, 

 p. 458, pi. -xiv, figs. 3a, 3b. 



Shell below medium size, very obliquely ovate, forming about two 

 very rapidly expanding volutions, which are contiguous, except near 

 the apertural margin ; whorls rather compressed, somewhat sharply 

 rounded along the periphery. Spire slightly elevated above the 

 level of the body whorl. Aperture ample, oval ; labrum sinuous. 

 Surface marked by undulating lines of growth and often by a few 

 low, obscurely defined ridges. 



Horizon and localities. Kinderhook beds : Richfield and Newark, 

 Ohio. 



This form is commonly found only as internal casts and the sur- 

 face markings are therefore rarely preserved. The species usually 

 does not have the labrum touching the spire, nor the latter as closely 

 coiled as is shown in the figures of IVIeek & Worthen. 



Capulus lodiensis (Meek). 



Platyceras i^Orthonychia) lodiense Meek, 1871. Proc. Acad. Nat. Sci., Phila., 

 1871, p. 170. 



Platyceras [Orthonyckia] lodiense Meek, 187.5. Geol. Sur. Ohio (Pals.), vol. 

 II, p. 313, pi. xiii, figs, la, lb. 



Shell l)elow^ medium size, obliquely conic, anterior slope moder- 

 ately convex, lateral slopes straight, or very slightly concave, pos- 

 terior slope concave ; a narrow rounded ridge extends anteriorly 

 from near the apex to the labrum. Aperture subelliptic ; margin 

 somewhat sinuous. Surface apparently marked by fine lines of 

 growth only. 



Horizon and localiixj. Kinderhook beds : Lodi, Ohio. 

 Capulus lodiensis seems to be very closely related to C. suhplica- 

 tus, with which it should, perhaps, be regarded as synonymous ; the 

 chief difference being simply the more plicate character of the lat- 

 ter. It has been elsewhere shown that the plications are extremely 



